The association between the Alpha Leonis system mentioned in "The Vengeance Factor" and the Regulus star and planets is based on reference material and the real world association. According to Star Trek Maps (p. 29), The Worlds of the Federation (p. 130) and Startrek.com, Alpha Leonis was the same system as Regulus. In the real world, Alpha Leonis is the Bayer classification name for Regulus.

According to the Star Trek: Star Charts (pp. 56,61,62), the Regulus (also known as Alpha Leonis) system was located in the Beta Quadrant. It was a trinary star system. Regulus A was a B-class star with a magnitude of +1, which was a hundred times brighter than Sol. Regulus B was a M-class star. Regulus C was a K-class star. In 2152, this system was in non-aligned space. By 2378, the system had been incorporated into Federation space, and was a destination on the major space lanes.

The Star Trek Encyclopedia (4th ed., vol. 2, p. 212) described Regulus as "a multiple star, the brightest of which is a blue-white main sequence star, located some 79 light years from Earth."